He relaxed and pointed a finger at the gang of camera-happy Indian fans gathered to watch him filming on the South Bank of the River Thames.

"No solo shots please," he told them as he grinned. Minutes later, he was posing with each member of the small, but adoring, crowd that had waited patiently as he rehearsed the last scene on the final day's shooting for Kabhi Khushi Kabhie Gham.

Later, he explained, "I don't permit solo shots because some people try to make money out of the pictures by selling them."

It was not a complaint, more a statement of fact by a superstar increasingly respected for both his acting techniques and his personal code of gentlemanly behaviour.

In Kabhi Khushi Kabhie Gham, he plays one of Amitabh Bachchan's two sons (the other son is Shah Rukh Khan). The film plot has Hrithik romantically linked with one of two sisters played by Kareena (the other is played by Kajol).

Or at least that's the way it looked on location with Big Ben and the British Houses of Parliament shimmering across the river and a speed boat making vroom! vroom! noises as it sped past in the dark.

The actual sequence we witnessed on the last day of shooting involved a tango-like dance movement in which Kareena, dressed in a bold red bikini top and matching leather trousers is swept off her feet by muscular Hrithik.

There were a few wolf whistles from the crowd as Hrithik and Kareena acted the scene for the umpteenth time.

One Japanese tourist, who had never heard of Hindi cinema, thought he was witnessing the love scene from a Latin American
melodrama.

In fact with the way they looked and they way they dressed, there was no way an uninformed foreigner could detect that the leading man and his leading lady were box office hot properties from the Indian film world.

Seconds later, Hrithik and Kareena hurried back to the television monitor around which director Karan Johar and his assistants were hunched.

It was no good. They had to do it all again.

This time, the colour of Kareena's lipstick had to be changed. Hrithik's hair was out of place and had to be brushed back. As the man with the make-up bag and the girl with the hairbrush finished their work, the cameras rolled again.

Less than 24 hours earlier, I had watched the couple as they acted out yet another sequence in the shadows of London's historic St Paul's Cathedral.

On that occasion, there was no dance, just sitting and talking in their silver Mercedes Benz convertible when constant exchanges of sultry looks simply did not seem to work on camera.

Astonished local onlookers could not believe what they were witnessing. At one point, a crowd of drunks roared past in their car, waving their fists and shouting obscenities.

But at St Paul's, there was another small crowd of Hindi cinema fans waiting with autograph books and cameras poised.

Once again, Hrithik did them proud.

Always poised and ever sober, he has few visible vices.Those of an older generation may fault him for his heavy smoking. But he would argue he needs the cigarettes for concentration.

The only time I have seen him look anxious is when his wife Suzanne is with him. At such times, his instinct is to stay as physically close to her as possible to the willowy beauty shield her from unwelcome attention.

On every other occasion, he has been fully in control, never letting down his guard.

Members of the camera crew speak admiringly of the cool he displayed in handling the 1,000 strong British-Asian crowd that managed to break through the security cordon during filming last week at London's Osterley Park.

They insist he did not bat an eyelid when 20 screaming teenage girls hurled themselves at him. On the contrary, they say, he posed for pictures and signed autographs as if nothing unusual had happened.

Back at the hotel over a cup of coffee, I asked him what he thought of his British fans. Hrithik took his time in answering.